It is known in this art to provide lubricious coatings for medical devices. Lubricious coatings are typically required for implantable or insertable medical devices such as hypodermic needles, surgical needles, trocar obturators, cutting devices, penetrating devices and catheters that are in contact with tissue. The primary purpose of such coatings is to ease the penetration or implantation of the device into tissue, often for multiples passes, cycles or cuts, e.g., surgical needles and scalpels.
Surgical needle and suture combinations are the mainstay of most surgical procedures. Conventional surgical needles are elongated members having curved configurations, distal piercing tips and proximal suture mounting ends. The surgical needles may have optional cutting edges as well. The suture mounting ends may consist of formed channels or drilled bore holes in which the end or ends of a surgical suture is mounted. The function of the surgical needles is to pierce, and in certain instances pierce and cut, tissue to create a channel or pathway for the surgical suture through tissue that the surgeon desires to approximate. Typically, multiple passes of the needle and suture through tissue are required to effectively approximate tissue surrounding a wound or opening, or to affix a prosthetic device such as a heart valve to tissue, etc. The suture frequently forms conventional stitches that are secured with conventional surgeon's knots.
As previously mentioned, it is known to coat surgical needles with conventional lubricious coatings. Such coatings include polymeric silicones and siloxane, including polymers such as polydimethylsiloxane, having various different end groups, molecular weight, along with additives such as cross-linkers, catalysts, etc. These additives to the coating ensure that the silicones have adequate adhesion and durability when used as a needle coating. Silicone coatings for medical devices including surgical needles are disclosed in U.S. Pat. No. 7,041,088 which is incorporated by reference.
It is know that surgical needles may experience diminished penetrative ability with each pass through tissue, possibly resulting in inconsistent performance. While the application of coatings (silicones, in particular) to needles often provides lubricity and durability, thereby extending their useful life, the application of the coatings may require a time-consuming process involving the deposition of a silicone solution and subsequent curing, including the evaporation of solvent(s), and thermal treatment. Although surgical needles have benefited from presently used coatings, there is a constant need in this art for further improvements that may enhance the use of surgical needles by surgeons in surgical procedures. In particular there is a need for improved lubricious coatings having improved characteristics including lubricity to reduce insertion and drag forces, durability to maintain the penetration performance, long term stability (package/or storage), biocompatibility, ease and efficiency of application and compatibility with sterilization method.